The Building Coder

Programmatic Access to Duct Sizes

Here is a nice little MEP related blog post on accessing duct sizes through the API to round off the week. It was provided by our MEP expert Martin Schmid, who says: I recently heard from a couple of developers that they had difficulties accessing the Duct Size settings in Revit. In the user interface, you can see them by selecting Manage > MEP Settings > Mechanical Settings > Duct Settings > Round/Oval/Rectangular. I threw together a macro to check... Read more →

Recursively Disable Architecture Mismatch Warning

I recently explained the cause and resolution of the processor architecture mismatch warning MSB3270. On closer consideration, I decided to fix it for all the ADN training material labs and samples, and actually for the entire collection of Revit SDK samples as well. This is obviously not something you want to do manually, considering that it involves a modification of hundreds of project files. Here are the steps involved in automating and testing this process: Disable mismatch warning utility Project... Read more →

Sun Direction, Shadow Calculation and Wizard Update

I enjoyed some wonderful hot sunny days since I returned from New England back to Switzerland. Summer finally arrived. A nice change after the rain and cold both here and in New Hampshire and Massachusetts. Talking about rain and sun leads up nicely to today's topic, on the sun direction and shadow calculation in a Revit BIM. Before I get to that, though, I present an update of my Revit add-in wizards resulting in part from yesterday's post on the... Read more →

Processor Architecture Mismatch Warning and Key Hook

In the past ten days, I migrated The Building Coder samples, ADN training labs, MEP and Structural sample material from Revit 2013 to 2014. In all of these migrations, I lamented the processor architecture mismatch warning MSB3270 saying There was a mismatch between the processor architecture of the project being built "MSIL" and the processor architecture of the reference "RevitAPI, Version=2014.0.0.0, Culture=neutral, processorArchitecture=x86", "AMD64". This mismatch may cause runtime failures. Please consider changing the targeted processor architecture of your project... Read more →

Units and RevitLookup

Here is a typical question from a Revit API newbie that prompts me to reiterate some important basic beginner information on units and the RevitLookup tool for exploring the Revit database: Question: How can I retrieve the length and mass units from a Revit document? Answer: The internal Revit database length unit is always imperial feet. That cannot be changed, so there is you answer for that. Similarly, the internal database unit for weight is kg, as far as I... Read more →

Determine Revit Demo Mode Revisited

Almost a year back, we talked about how to determine whether the current running Revit application is a demo version or not. The initial suggestion was to test this by trying to execute real functionality modifying the model and then save it. That obviously incurs significant overhead and may cause other problems as well. Rudolf Honke suggested simply reading and evaluating the Revit main window title text instead. Now Madmed created and posted an implementation of Rudolf's idea. I took... Read more →

Categories Collection Item Accessor Fails

The document settings categories collection Item property returns null for certain built-in categories, and even throws an exception for certain others. You should be aware of this. I mentioned a related issue back in the Revit 2011 timeframe, describing The Building Coder CmdCategories sample command. Still, this is a bit unexpected and has caused issues for several developers. Here are some examples: Question 1: For some reason I cannot obtain the category for stacked walls, e.g. using Dim cat As... Read more →

Determine Revit Demo Mode

Here is yet another interesting example of an apparent gap in the Revit API that can be easily filled using a little workaround. We have seen numerous examples of performing a certain operation within a temporary transaction that is then rolled back to cancel it, such as to determine gross material quantities for an element with openings, a host reference and, more generally, all object relationships. Here is an example of using a related but different approach: the trick consists... Read more →

Rotate True North

We have previously looked at how to handle the project location properties and more specifically how to handle the effect of a rotated Project North on an element azimuth. Here is a question on the 'opposite' topic, how to set up a project north rotation in the first place: Question: Is there any way to rotate the truth north using the Revit API? It can be done in the user interface using the Manage > Project Location > Position >... Read more →

Family Instance Room Phase

We already looked at some examples of confusion due to the interaction of phases with the room property on family instances. Here is a new aspect of this encountered and solved by Patrick Rosendahl of SOLAR-COMPUTER GmbH, who kindly explains the issue and its resolution like this: Problem: I am having a problem with the FamilyInstance Room property. I looked at the discussion of issues with the Room property and its phase dependency but have not been able to solve... Read more →

Set New Pipe Type Properties

Here is an interesting Revit MEP API question on setting the preferred elbow, tee and junction type information after creating a new Revit MEP pipe type, answered by my colleague Joe Ye in Beijing: Question: I am creating a new Revit MEP pipe type by filtering for all element types of the category OST_PipeCurves and selecting the one named "Standard". On the resulting new ElementType instance, I would like to define the preferred settings as follows: Change the preferred elbow... Read more →

Locking the Add-Ins Ribbon Tab

Here is a minute user interface question of interest to developers that comes up from time to time: Question: When I select an element in the Revit model, the ribbon tab is always switched. Is there any way to keep 'Add-Ins' tab focused at all times? Answer: Here are two little tricks that might help: Drag the panel you wish to have available off the ribbon add-ins tab somewhere else on the screen. It will then remain available at all... Read more →

Visual Studio, C# and VB Express

Yesterday Kean mentioned that debugging AutoCAD.NET projects using the Visual C# and VB Express editions is now directly supported by the latest version of the AutoCAD .NET Wizard. That prompted me to have a look and see what the current situation is with Revit add-ins. Obviously, we poor Revit developers do not have such a sophisticated wizard available ... or so I thought! I installed Visual C# Express and started my experiment: I launched the new installation and selected New... Read more →

Set Copy Local to False

I cannot count the number of times I have pointed out that the Copy Local flag should be set to false on the Revit API assembly references. Here are some of the numerous previous examples and explanations of this: A C++ Revit add-in Selection watcher using Idling event The DevTV add-in templates Pipe to conduit converter Custom ribbon tab Porting from C# to VB.NET Exporting a family instance to gbXML Application events in VB Debugging a Revit add-in The SDK... Read more →

Retrieving Materials

Some people have reported issues using the Document.Settings.Materials collection. For instance, its Contains method may throw an exception when used with Revit Structure 2012, while it works fine with Revit Architecture 2012. The problem actually probably has nothing to do with the flavour of Revit being used, but is caused by the template file that the project is based on. If you retrieve materials in a project based on the architectural template in Revit Structure, it also works fine. In... Read more →

Point Cloud Snap and Freeze

Here are some questions that came up a while ago regarding point clouds: Question: As far as I can tell, the standard object snap settings also control snapping to point clouds: Is there any way to snap to individual points in the point cloud? Answer: Revit itself never asks for the pick of an individual point in a point cloud, so there is no mechanism to support this in the API either. Even when Revit prompts the user to pick... Read more →

Text Size

I am back again from the Autodesk European Football Tournament 2011 in Verona, Italy, vividly described in more detail by Kean on his blog. We were both part of the combined Global Services (to which we of ADN belong) and Worldwide Marketing team: Back to the Revit API, we already looked at some aspects of text formatting such as textnote alignment and rotation. Here is a still more immediate and simpler issue: Question: I created some text using the NewTextNote... Read more →

Implicit Line Continuation in VB 2010

An new feature that is of interesting to us VB Revit add-in developers is the implicit line continuation that was added in Visual Basic 2010. In prior versions of VB, all statements that continue beyond the end of the line have to be explicitly marked using an underscore '_' character. Since some of the Revit API method signatures force rather long lines, this can become a bit overwhelming. This is what it might look like in VB 2008: '''

... Read more →

Set the Visual Style of a View

Today is the day of the Chinese Revit API webcast, and also the holiday of Ascension Day in many part of Europe. Just like last year, it is raining cats and dogs again. Anyway, here is a useful answer to a little question that arises from time to time: Question: I'm creating a new 3D view of a family instance like this: Dim v As View3D = doc.Create.NewView3D( _ famInst.FacingOrientation) v.SectionBox = famInst.BoundingBox(v) Now I would like to set its... Read more →

Set Preview Image

While I am away, here is a useful article to keep you occupied by my colleague Saikat Bhattacharya: Setting preview image/view for a Revit document using Revit 2012 API Question: How can I set the preview image/view for a Revit document using the Revit 2012 API? In particular, when I load an older version of Revit document and do a SaveAs using the API, how can I set its preview image? Answer: There are two ways to set a preview... Read more →

Product GUIDs for Revit 2012 and Forever More

Every year anew, people ask for the Revit product GUIDs used to identify the Revit installation and stored in the Windows registry under HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Uninstall There are different keys for each of the three Revit flavours, and for both 32 and 64 bit operating systems. The first time around, we discussed the Revit 2010 and previous versions' installation path and product GUIDs, and then updated the list for Revit 2011 last year. As I mentioned last time, the install path is... Read more →

Visual Studio Add-In Wizards for Revit 2012

As I mentioned yesterday, this weekend was spent traveling to Verona to give a Revit API training here. Happily, I enjoyed some mountain air the weekend before, on Helgenhorn 2837m, Basodino 3273m and Cima di Lago south of All'Acqua in the Bedretto Valley (more photos by Jogi): Anyway, that was last weekend; back to here and now in Verona, where I was busy yesterday, preparing for the training, starting today. I already updated the DevTV Visual Studio wizards for creating... Read more →

Performant Hardware

I spent all day yesterday in trains, which was unfortunate, since it was the most beautiful Sunday, and springtime is in full bloom. It also forced upon me some unfortunate comparisons of the Swiss and Italian train systems. Needless to say, I arrived later than expected. Still, I ended up happily back in Verona, Italy, where I started seriously learning Italian two years ago, for a repeat visit to provide a Revit API training class to Steel & Graphics srl.... Read more →

Nested Lighting Fixture Instances

We already looked at a couple of aspects of nested family instances, such as access to nested instance geometry, creating nested families and determining whether a family instance is nested. Now Joel Spahn of Lighting Analysts, Inc. submitted a comment on the nested family utility methods raising a new question related to nested lighting fixtures, efficiently resolved by Harry Mattison of the Revit development team: Question: I have adapted this code to extract nested family instances and it works beautifully.... Read more →

Change Element Colour

We once looked at changing the colour of model or detail curves by setting their category line style. Here is another simple little question, on setting the colour of an element, with a clear and simple answer, also by Joe Ye: Question: How can I programmatically change the colour of an annotation symbol, e.g. a tag, in a Revit project? Answer: You can change the colour of individual elements in a specified view using the View class ProjColorOverrideByElement property. It... Read more →

Internal Imperial Units

To start off this week, here is a pretty useless question that still seems to be of great interest to many people: Question: Odd question perhaps, but why does Revit internally work in imperial units? Answer: I do not find your question odd at all; many others wonder that as well, I am sure. Briefly, I would hazard that the answer is simply that this is a religious question, or a question of taste, or historically evolved. Does that satisfy... Read more →

Reducing Revit Debug Verbosity

Many people have complained about the amount of noise caused by the ribbon in the Visual Studio debug output window. Kean Walmsley just pointed out that you can easily make AutoCAD less noisy when debugging by adding a couple of lines to the acad.exe.config file, which lives in the same folder as the acad.exe you are debugging, such as C:\Program Files\Autodesk\AutoCAD 2011, to ask the WPF binding trace provider to lower the volume. Since Revit uses the same internal ribbon... Read more →

External Application Attributes

Arnošt Löbel added a comment on the little zero document external application that I presented last week, pointing out that the transaction attribute (e.g. TransactionMode.Manual) is only applicable to external commands, not applications. As he says, it should be treated as an add-in declaration error, but since it is harmless, it is quietly ignored. (It could be treated as an error in the future though.) The question is also how the regeneration attribute is handled. It was originally intended for... Read more →

Phase Dependent Room Properties

Here is a recent query from a developer on the family instance FromRoom and ToRoom properties. He asked: Question: I am unable to retrieve the room associated with certain door and window instances. I attached a Revit model where the family instance room properties return "null", even though the doors are associated with a room. Why do the ToRoom and FromRoom family instance properties return "null" for these doors? Answer: I analysed your model and see no issues with the... Read more →

Automate DesignOption and 64 Bit Add-In Templates

Let's start off the week with another idea from Rudolf Honke of acadGraph CADstudio GmbH. He recently presented his results of exploring the Revit ribbon internals using UISpy, driving Revit using UI Automation, subscribing to UI Automation events, and switching between different projects and views. Here is another of his ideas of making use of UI Automation: This screen snapshot shows the design options dropdown list: When showing elements programmatically using the app.ActiveUIDocument.ShowElements( elementSet ) method, it might occur that... Read more →

84 Second Product Support Overview

As you know, I work in the AEC workgroup of the ADN or Autodesk Developer Network DevTech organisation, providing support to developers making use of Autodesk products and their application programming interfaces (APIs). ADN is part of the Autodesk support organisation. Another, much larger part of the support organisation is the product support team, which resolves end user issues. For a really quick overview of the E-Services provided by Autodesk Product Support, you can have a look at this new... Read more →

Finding Connected Structural Elements

We had some glimpses in the past of the structural analytical model maintained by Revit Structure, e.g. when looking at The AnalyticalViewer SDK sample Revit Structure API Resources The NewLineLoad method Analytical support tolerance An overview of geometry options The Revit Structure 2011 API Here is a very basic question that can be addressed using the analytical model: Question: Is there any way to find connected structural elements? For example, to find columns from a connected beam, or beams from... Read more →

Read DWG Settings and Content Location from INI File

Autumn is here in full now, grey and wet outside. The beautiful yellow leaves are turning brown and soggy. We had a wonderful sunny weekend, though, and I lay on the grass in the sunshine watching the distant mountains yesterday... In a completely different vein, today is the final day for submitting the Autodesk University material! I'm still not completely done... Meanwhile, here are two quick cases handled by Joe Ye quite a while back which both ended up resorting... Read more →

C++ Revit Add-In

To my great surprise, I recently discovered that I have never yet published anything at all on implementing a Revit add-in in C++. That is way overdue, so here goes, a step by step description of setting up a C++ project to implement a Revit 2011 external command add-in. It is very similar to setting up a C# or VB Revit add-in project, similar to the steps described for a C# or VB Revit add-in for Revit 2009 way back... Read more →

Network Access to Add-In Manifest and Icons

We already discussed quite a few aspects of the add-in manifest files, including: A simple example of creating one for my first Revit 2011 plug-in, the pipe to conduit converter. The RevitAddInUtility which can be used to read and write add-in manifest files. My Guidize utility which can populate the add-in manifest ClientId GUID. A Guidize update which also handles the AddInId tag. The visibility mode which controls which in which Revit editor contexts an external command add-in appears. How... Read more →

Setting a Locked Parameter

I arrived back in Europe and am still working through my pile of email. Here is another interesting tidbit that arose in the course of some correspondence with Anthony Forlong, Associate and CAD Manager at Clendon Burns & Park Ltd over the past few days: Question: I've written an application that lets our users search our network and insert Revit families and load types from type catalogues. To help increase performance I have been using the duplicate method if the... Read more →

Add New Materials from List

I am happily back from Siem Reap in Cambodia and the ruins of Angkor Wat (more photos): Yesterday I visited the Grand Palace and the reclining Buddha in Wat Pho in Bangkok (more photos): Angkor Wat and Cambodia was absolutely wonderful, and I am really glad that I went there. The places I visited in Thailand were rather touristy, whereas in Cambodia I had the feeling of getting much more in touch with real people and life: Before going there... Read more →

Editing Elements inside Groups

Today is the last day here with my brother Marcus in Pattaya. We had a look at the Sanctuary of Truth yesterday and I posted some photos from the beach in front of it, which was surprisingly quiet and lonely: Early tomorrow morning I will be heading off towards Cambodia and Angkor Wat, then spend a day or two in Bangkok, and return back here again to pick up my parked things before heading back to the airport. I am... Read more →

Debugging in Visual Studio 2010 Express

Yesterday was the first day of the Revit API training in Munich. As usual, I was able to learn something new. Frank Neuberg of MAX BÖGL assembled and tested the following summary of information sources related to using Visual Studio 2010 and its Express version for creating and debugging a Revit add-in. I've summarized some information sources to set up an integrated debugging process for class library projects together with Revit.exe (2011) in C# Visual Studio 2010 Express Edition: Currently... Read more →

DevTV Add-In Templates

Here are the add-in templates prepared by my colleague Augusto Gonçalves of Autodesk Brazil for the upcoming DevTV presentations. I really love both the implementation and the description, both are so short and sweet and yet complete! They save you a lot of typing and clicking when setting up a new add-in, and especially help avoid all the potential errors that insist on creeping in when you set things up manually. Support is provided for both external commands and external... Read more →

Family Element Visibility

Here is a question on programmatically setting the visibility of an element in a family document: Question: I need to assign a Yes/No parameter to the visibility property of a family feature, e.g. an extrusion element. I need to do this to suppress a specific extrude feature for certain types. I know how to do it manually, by selecting the feature and then clicking the visibility toggle in the element properties. How can I achieve it through the API? Answer:... Read more →

Visual Studio 2010 and the .NET Framework

In section 1.6 'Supported Programming Languages', the developer guide "Revit 2011 API Developer Guide.pdf" in the Revit SDK clearly states that "The Revit Platform API is fully accessible by any language compatible with the Microsoft .NET Framework 3.5, such as Visual Basic .NET or Visual C#." In section 1.3 'Requirements', it also mentions that the programming environment recommended for going through the examples is Visual Studio 2008. That is also the environment used to create and compile all the SDK... Read more →

Debugging with Visual Studio 2010 and RvtSamples

Rod Howarth just published a description of a problem debugging a Revit 2011 add-in with Visual Studio 2010. He found a related thread on the Microsoft Connect Visual Studio discussion forum describing the same issue with Revit 2010 and presenting a solution for it: The issue that you are encountering is that Visual Studio 2010 is launching Revit under the default debugger (v4.0) but since you are building a project against the 2.0 framework (3.5 runs on the CLR 2.0)... Read more →

Project Location

This is part 8 of Scott Conover's AU 2009 class on analysing building geometry, dealing with the project location and its effect on element transformations. We aready looked at the project location in the discussion on unrotate north. However, as Scott pointed out, the results presented there are somewhat misleading and are subsumed by the following discussion. The project location obviously also affects the azimuth of an element, i.e. the angle between the element and true north, and our previous... Read more →

Retrieving Project Parameters

In between the series of background information from Scott's Autodesk University presentation on analysing building geometry, let's have a quick look at a completely different question, on retrieving all shared parameters from a Revit project. Other posts related to shared parameters are listed at the end of our discussion of RDBLink Export. The following solution comes from a case handled by Saikat Bhattacharya. Question: How can I programmatically retrieve the set of project parameters added to a given Revit project?... Read more →

Model and Detail Curve Colour

We have had several questions on how to change the colour of model or detail curves. Here is an answer to this question from a recent case handled by Joe: Question: I am drawing a detail arc using the Revit API DetailArc class and trying to change its properties like colour, graphic style etc. How can this be achieved? Answer: You can change the detail arc line colour by changing the colour of the detail curve category's line style. Here... Read more →

Vertical Projection of Beam Analytical Model

We tried to fly from Milano to Paris this evening for the last DevDays conference, but unfortunately our flight was cancelled due to snow in Paris. Now we are stuck at the Milano airport and hoping that the first flight in the morning will not be cancelled as well. If it is, we will not be able to make it at all. Otherwise, we will arrive rather late and have to reschedule the agenda, but at least then we will... Read more →

Parameter Filter Units

The Western European DevDays conference tour has begun, and I will be presenting and travelling all week, leaving very little time to spend blogging or responding to comments. I visited relatives in London the preceding weekend, and took some time to write and post this before the real crunch began. Several previous posts deal with various aspects of unit handling in the Revit API: Units. Formatting unit strings. Unit types and format options. Unit conversion. Unit Suffix and the ProjectUnit... Read more →

Distinguish Different Dimension Types

I am back in Europe again after spending most of the weekend travelling, similarly to Kean but in the opposite direction. In his last post, Kean summarised some interesting views on the evolution of Autodesk University. Returning to the Revit API, here is a nice can-do solution presenting a workaround created by my colleague Joe Ye of Autodesk and Henrik Bengtsson of Lindab on how to distinguish between the different kinds of dimension types. Question: I am creating a drafting... Read more →

Crop 3D View to Room

In case you have heard enough about both climbing and AU and AUv in the last few posts and would prefer to read about the Revit API and nothing but the Revit API, here is something for you. This is based on a recent case handled by Joe Ye and deals with the 3D view crop box and the transformations required to set it up properly, an issue we have never previously looked at. Question: I would like to set... Read more →